.net - TLS handshake with a smartcard fails randomly -
i have windows service periodically connects host using .net socket class. it's standard tcp/ip connection using smtp protocol. the connection secured certificate stored on smartcard. i'm using sslstream class handle ssl stuff. this works of time. @ random point of time, authentication fails. error: a call sspi failed, see inner exception. error type: system.security.authentication.authenticationexception server stack trace: @ system.net.security.sslstate.endprocessauthentication(iasyncresult result) @ system.threading.tasks.taskfactory`1.fromasynccorelogic(iasyncresult iar, func`2 endfunction, action`1 endaction, task`1 promise, boolean requiressynchronization) inner exception: system.componentmodel.win32exception local security authority cannot contacted after failed attempt, authenticationexcpetion remains, inner exception changes: a signature operation must performed before user can authenticate at point have restart service , connect flawlessly. ssl ha...